There were 1965 Quarters coined onto silver planchets and the weight would be heavier than the clad version. 6.25 grams. So your coin is in the correct weight range, but it doesn't look silver to me (looks like nickel). The normal clad planchet is 5.67 grams so a plated quarter could weigh around 6 grams. I think you need to do a silver test with tissue paper for starters and wait for folks with more knowledge to chime in and get you started on things you can do to figure out what you have there.





























